Foxit eSign MCP Server

An MCP (Model Context Protocol) server that connects Claude to the Foxit eSign API — send, track, and manage e-signature envelopes without leaving your conversation.

Ask Claude things like:

• "Send this NDA to [email protected] for signature"
• "What contracts are still waiting to be signed?"
• "Cancel the vendor agreement I sent yesterday"
• "Download all signed leases from last month"
• "Use our standard offer letter template and send it to the new hire"
• "Generate this contract and send it — embed the signature fields directly in the document"
• "Save as draft and give me the editor link so I can place fields myself"

Quick install (Claude Desktop)

Requires Node.js 18+ and Claude Desktop.

claude mcp add foxit-esign-mcp \
  -e FOXIT_CLIENT_ID=your_client_id \
  -e FOXIT_CLIENT_SECRET=your_client_secret \
  -e FOXIT_BASE_URL=https://na1.foxitesign.foxit.com/api \
  -- npx -y foxit-esign-mcp@latest

Restart Claude Desktop. That's it — all 17 tools are available immediately.

Get your Client ID and Client Secret from the Foxit eSign dashboard → Settings → API Keys.

Or run the setup wizard

Prefer not to wrangle command-line flags? Run the interactive wizard — it collects your credentials, verifies them against the Foxit API, and patches your Claude Desktop / ChatGPT Desktop config automatically (merging in without disturbing any other MCP servers you already have):

npx foxit-esign-mcp setup

Non-interactive (CI / scripted):

npx foxit-esign-mcp setup \
  --client-id=your_client_id \
  --client-secret=your_client_secret \
  --region=na1 \
  --apps=claude,chatgpt

Add --no-verify to skip the credential check. Restart your desktop app afterward.

What's included

17 tools across two categories:

| Category | Tools | |----------|-------| | Envelopes | send document (URL / base64 / local file), list by status, get details, batch details, search by name, send reminder, view activity, send draft, download files, cancel, delete, stale envelopes, expiring soon | | Templates | list templates, get template details, send from template, create template from PDF |

See docs/TOOLS.md for the full reference with parameters and example prompts.

Key features

AI-assisted field placement

Claude reads your PDF, finds signature lines, date blanks, and initials boxes, then places all fields automatically in a single API call — no drag-and-drop required.

"Send contracts/nda.pdf to [email protected] for signature"
→ Claude reads the PDF, scores field confidence, places all fields, sends immediately

Text tag support (AI-generated documents)

When Claude generates a document, it can embed Foxit text tags directly in the content. Foxit converts them to form fields automatically — no coordinate math needed.

"Draft a consulting agreement with ABC Corp and send it to [email protected]"
→ Claude generates the PDF with ${signfield:1:y:____} tags embedded,
  sends with processTextTags:true — fields appear exactly where the tags are

Fast draft path

Not sure where the fields go? Tell Claude to save as draft. It returns a visual editor link in ~2 seconds so you can drag-and-drop fields yourself.

"Save this as a draft — I'll place the fields myself"
→ Returns draftEditUrl in ~2s, no field analysis run

Dual transport

| Mode | Transport | Use case | |------|-----------|----------| | Local | stdio → Claude Desktop | Your machine, your credentials | | Cloud | HTTP → Vercel + claude.ai | Shared deployment, per-user OAuth |

Supported regions

| Region | Code | API base URL | |--------|------|--------------| | United States | na1 | https://na1.foxitesign.foxit.com/api | | Canada | na2 | https://na2.foxitesign.foxit.com/api | | Europe | eu1 | https://eu1.foxitesign.foxit.com/api | | Australia | au1 | https://au1.foxitesign.foxit.com/api |

In cloud mode the user selects their region on the OAuth consent page — no server configuration needed.
In local mode set FOXIT_BASE_URL to the correct regional endpoint.

Installation options

Option A — npx (recommended, always latest)

claude mcp add foxit-esign-mcp \
  -e FOXIT_CLIENT_ID=your_client_id \
  -e FOXIT_CLIENT_SECRET=your_client_secret \
  -e FOXIT_BASE_URL=https://na1.foxitesign.foxit.com/api \
  -- npx -y foxit-esign-mcp@latest

This pulls the latest version from npm on every startup. No git clone, no build step.

Option B — Manual Claude Desktop config

If you prefer to pin a version or manage the config yourself, edit your Claude Desktop config file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "foxit-esign-mcp": {
      "command": "npx",
      "args": ["-y", "foxit-esign-mcp@latest"],
      "env": {
        "FOXIT_BASE_URL": "https://na1.foxitesign.foxit.com/api",
        "FOXIT_CLIENT_ID": "your_client_id_here",
        "FOXIT_CLIENT_SECRET": "your_client_secret_here"
      }
    }
  }
}

Restart Claude Desktop after saving.

Option C — Build from source

git clone https://github.com/niketchoudhary/FoxiteSignMCP
cd FoxiteSignMCP/foxit-esign-mcp
npm install
npm run build

Then add to Claude Desktop config pointing to the absolute path of dist/index.js:

{
  "mcpServers": {
    "foxit-esign-mcp": {
      "command": "node",
      "args": ["/absolute/path/to/foxit-esign-mcp/dist/index.js"],
      "env": {
        "FOXIT_BASE_URL": "https://na1.foxitesign.foxit.com/api",
        "FOXIT_CLIENT_ID": "your_client_id_here",
        "FOXIT_CLIENT_SECRET": "your_client_secret_here"
      }
    }
  }
}

Option D — Vercel (cloud deployment for claude.ai)

Deploy as a serverless function so any claude.ai user can connect with their own Foxit credentials via OAuth.

1. Deploy

npm install
npx vercel --prod

The MCP endpoint will be live at:

https://your-project.vercel.app/mcp

Set the JWT secret for session signing:

vercel env add OAUTH_JWT_SECRET
# Value: openssl rand -base64 32

2. Connect in claude.ai

Go to Settings → Connectors → Add custom connector:

| Field | Value | |-------|-------| | Name | Foxit eSign | | Remote MCP server URL | https://your-project.vercel.app/mcp | | OAuth Client ID | Your Foxit Client ID | | OAuth Client Secret | Your Foxit Client Secret |

How the OAuth flow works

1.  Claude hits /mcp → server returns 401 + WWW-Authenticate
2.  Claude fetches /.well-known/oauth-protected-resource
3.  Claude fetches /.well-known/oauth-authorization-server
4.  Claude opens /authorize in the user's browser
5.  User selects region + clicks "Authorize Access"
6.  /authorize issues a short-lived auth code JWT containing region
7.  Claude POSTs auth code + credentials to /token
8.  /token verifies JWT, fetches Foxit token, wraps {foxit_token, region}
    into a signed session JWT returned as the access_token
9.  Claude retries /mcp with Authorization: Bearer <session_jwt>
10. /mcp decodes session JWT → routes to correct regional Foxit API

Each user authenticates with their own Foxit account. Nothing is stored server-side.

Environment variables

Local / Claude Desktop

| Variable | Required | Description | |----------|----------|-------------| | FOXIT_BASE_URL | No | Regional API base URL. Defaults to NA1. | | FOXIT_CLIENT_ID | Yes* | OAuth2 client ID from Foxit developer portal | | FOXIT_CLIENT_SECRET | Yes* | OAuth2 client secret from Foxit developer portal | | FOXIT_BEARER_TOKEN | Yes* | Pre-fetched bearer token. Auto-fetched if absent. |

*Either FOXIT_BEARER_TOKEN or both FOXIT_CLIENT_ID + FOXIT_CLIENT_SECRET are required.

Vercel (cloud)

| Variable | Required | Description | |----------|----------|-------------| | OAUTH_JWT_SECRET | Yes | base64-encoded 32+ byte secret for signing session JWTs. Generate: openssl rand -base64 32. |

Development

# Live reload (stdio — Claude Desktop mode)
npm run dev:stdio

# Live reload (HTTP — local Vercel handler testing)
npm run dev:http

# Build TypeScript → dist/
npm run build

# Type-check all targets without emitting
npm run typecheck

# Run live API tests (requires .env.local with credentials)
npm run test

# Read-only integration test (safe to run any time)
npm run test:integration

# Interactive browser-based tool inspector
npx @modelcontextprotocol/inspector node dist/index.js

Project structure

src/
  app.ts                    — MCP server factory; registers all 17 tools + field_placement_guide prompt resource
  index.ts                  — stdio entry point (Claude Desktop / npx)
  server.ts                 — Express HTTP entry point (local testing)
  client.ts                 — FoxitClient — auth, token refresh, typed HTTP helpers
  types.ts                  — TypeScript interfaces for all API response shapes
  constants.ts              — REGIONS map, CHARACTER_LIMIT, REQUEST_TIMEOUT_MS
  tools/
    folders.ts              — 13 envelope tools
    templates.ts            — 4 template tools
    fieldPlacementGuide.ts  — Full field placement reference (text tags + coordinate rules)
    utils.ts                — Shared helpers: truncate, formatDate, flattenPdf, rasterizePdf, etc.

api/
  mcp.ts                    — Vercel MCP handler (JWT auth, per-request FoxitClient)
  authorize.ts              — OAuth consent page (/authorize)
  token.ts                  — OAuth token exchange (/token)
  oauth-metadata.ts         — /.well-known/oauth-authorization-server
  oauth-protected-resource.ts — /.well-known/oauth-protected-resource

docs/
  TOOLS.md                  — Full tool reference with parameters and example prompts
  FIELD_PLACEMENT_SKILL.md  — Field placement rules, coordinate tables, confidence scoring
  FOXIT_API_REFERENCE.md    — Complete Foxit eSign REST API reference
  ARCHITECTURE.md           — Sequence diagrams, JWT formats, PDF pipeline, security controls

Notes

• All tools verified against the live Foxit NA1 API
• Responses over 25,000 characters are truncated with a continuation hint
• foxit_send_document with source: "local_file" works in local (stdio) mode only — the server must have filesystem access to the PDF path
• Token refresh is handled automatically on 401 responses in stdio mode
• PDFs with non-embedded fonts are auto-rasterized for rendering compatibility (requires Python 3 + PyMuPDF)
• PDFs with AcroForm / XFA interactive fields are auto-flattened before sending